CVE-2021-3455 Disconnecting L2CAP channel right after invalid ATT request leads freeze
An attacker can cause a system freeze by disconnecting an L2CAP channel immediately after sending an invalid ATT request in Zephyr RTOS.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-3455?
CVE-2021-3455 is a medium-severity use after free vulnerability in Zephyrproject Zephyr, published on 19 Oct 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Disconnecting L2CAP channel right after invalid ATT request leads freeze. Zephyr versions >= 2.4.0, >= 2.5.0 contain Use After Free (CWE-416). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp
Weakness: CWE-416
Which versions are affected by CVE-2021-3455?
It affects 1 product.
Products include Zephyrproject Zephyr.
How do I fix CVE-2021-3455?
No fix has been published for CVE-2021-3455 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2021-3455 being exploited?
There is no known exploitation of CVE-2021-3455 in the wild and no public exploit code.
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